Tülay TUNCA, Nesrin GÜRSAN, Hülya AKSOY, Nazım DOĞAN

Asit aspire ettirilen tavşanlarda pron pozisyonunda mekanik ventilasyon uygulamasının oksijenlenme ve akciğer histolojisine etkisi

Bu çalışmada asit aspirasyonuna bağlı akut respiratuvar distres sendromu (ARDS) modelinde, pron pozisyonunda mekanik ventilasyon tedavisinin, oksijenlenme ve akciğer histolojisine etkisini değerlendirmeyi amaçladık. Yeni Zelenda tipi 40 tavşanda pH=2.5 olan hidroklorik asitten 1 ml $kg^-1$ aspire ettirilerek deneysel ARDS modeli oluşturuldu. Denekler rastgele olarak iki eşit gruba ayrılarak (n=20), yarısı pron pozisyonda (Grup P) diğer yarısı (n=20), supin pozisyonda (Grup S) olacak şekilde, 4 saat süre ile aynı ventilator ayarlarında ventile edildi. Kan basıncı, kalp hızı ve arteryel kan gazlan monitorize edildi. Çalışmanın sonunda iki gruptaki tüm deneklerin akciğerleri çıkarılarak patolojik inceleme yapıldı. Akciğerlerdeki makroskopik ve mikroskopik bulgular grade 1,2, ve 3 olarak kaydedildi. Grup S ve Grup P arasında kan basıncı ve kalp hızı bakımından istatistiksel farklılık yoktu (p>0.05). Pron pozisyonundaki kan pH'sı ve parsiyel arteryel oksijen basıncı, supin pozisyomındakinden istatistiksel olarak anlamlı derecede yüksekti (p

Anahtar Kelimeler:

Oksijen, Ventilatörler, mekanik, Akciğer, Solunum güçlüğü sendromu, erişkin, Modeller, hayvan, Modeller, teorik, İnhalasyon, Tavşanlar, Asitler

Influence of mechanical ventilation in prone position on the lung histology and oxygenation in rabbits with acid aspiration

In this study we aimed to evaluate the influence of mechanical ventilation treatment in prone position experimentally on lung damage and oxygenation in an acid aspiration model of acute respiratory distress syndrome (ARDS). The experimental model of ARDS was induced by aspirationed of 1ml $kg^-1$ HCl (pH=2.5) in 40 New Zeland rabbits. The animals were randomly avocated into two groups. The animals were ventilated in either the supine or prone positions for 4 hours, using the same ventilatory settings. Blood pressure, pulse and arterial blood gases were monitorized. The lungs of all ani-mals in both groups were removed at the end of the study. Gross and microscopic evidence of lung injury was recorded as grade 1, 2 and 3. Considering blood pressure and pulses, there was no statistically significant difference between Group S (supine) and Group P (prone) (p>0.05). PaO2 and pH values in Group P were significantly higher than Group S (p<0.05 ). The lung injury in Group P was gradeI 2, in Group S was grade 2-3 (p<0.05). In conclusion, this study showed that prone positioning during mechanical ventilation in an acid aspiration model of acute respiratory distress syndrome reduces acid aspiration induced pulmonary damage and improves oxygenation.

Keywords:

Oxygen, Ventilators, Mechanical, Lung, Respiratory Distress Syndrome, Adult, Models, Animal, Models, Theoretical, Inhalation, Rabbits, Acids,

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